A wireless communication network may include, for example, a wireless Access Point (AP) and multiple wireless communication stations able to communicate using a wireless medium. A communication collision may occur, for example, when a first wireless station and a second wireless station transmit data at substantially the same time.
To reduce communication collisions, a Collision Avoidance (CA) mechanism may be used. For example, a wireless station may avoid transmission for a “backoff” period of time, determined individually by the station based on a pseudo-random number of units between zero and a pre-defined maximum Contention Window (CW) parameter. Accordingly, a first station may avoid transmission for a first pseudo-random backoff period, and a second station may avoid transmission for a second, different, pseudo-random backoff period, thereby avoiding collision between the transmissions of the first and second stations. Furthermore, a retransmission procedure may be invoked upon detecting a communication collision.
Unfortunately, when multiple stations contend simultaneously for a wireless medium, the CA mechanism and/or the retransmission procedure may result in poor network performance, e.g., poor network throughput, which may not be resolved by adjusting the CW parameter. For example, setting the CW parameter at a low value may increase contentions, whereas setting the CW parameter at a high value may result in long transmission delays.